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LD EIR,A
LD IIR,A     Load     Rabbit 2000/3000/4000/5000 Instruction

Opcode	Instruction	Operation
ED 47	LD EIR,A	EIR = A
ED 4F	LD IIR,A	IIR = A

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 2000/3000/4000	4	n/a	n/a
Rabbit 5000	4	4	2

Flags				ALTD			IOI/IOE
S	Z	L/V	C	F	R	SP	S	D
-	-	-	-

Description

• LD EIR,A: Loads the External Interrupt Register, EIR, with A. The EIR is used to specify the most significant byte (MSB) of the External Interrupt address. The value loaded in the EIR is concatenated with the appropriate External Interrupt address to form the 16-bit ISR starting address.

• LD IIR,A: Loads the Internal Interrupt Register, IIR, with A. The IIR is used to specify the most significant byte (MSB) of the Internal Peripheral Interrupt address. The value loaded in the IIR is concatenated with the appropriate Internal Peripheral address to form the 16-bit ISR starting address for that peripheral.